Major roads drive higher raptor mortality: insights from long-term rehabilitation data

Road expansion represents a growing threat to biodiversity, particularly within urban and peri-urban landscapes where wildlife movements intersect with transportation networks. Raptors are especially vulnerable to vehicle collisions due to their hunting behaviour and use of roadside habitats, yet empirical evidence from the UK remains limited. Here, we use admissions data from wildlife rehabilitation centres (WRCs) in England and Wales to examine patterns and outcomes of raptor-vehicle collisions. We analysed 586 geo-referenced admissions involving 10 raptor species between 2001–2019, assessing how species, road type (minor vs. major), season, landscape type and age influence mortality outcomes. Most collisions occurred on minor roads, however, collisions on major roads were substantially more lethal. Raptors struck on major roads had approximately 2.7 times higher odds of mortality than those struck on minor roads, highlighting an important distinction between collision frequency and collision severity. Relative to their breeding population sizes, Tawny Owl ( Strix aluco ), Western Barn Owl ( Tyto alba ) and Common Buzzard ( Buteo buteo ) were disproportionately more likely to be admitted to WRCs following collisions with road vehicles than expected by chance. Raptor-vehicle collisions remained relatively stable, highlighting the persistent threat that roadways pose for raptors over time. This study provides the first multispecies assessment of raptor-vehicle collisions across road networks in the UK. Our findings emphasise the disproportionate impact of major roads on raptor survival and highlight the need for targeted mitigation actions, including verge management and strategic speed reductions, within urban and peri-urban ecosystems.